October 2006 arXiv papers — page 27

G. Gyorgyi, N. R. Moloney, K. Ozogany, Z. Racz

Numerical and analytical results are presented for the maximal relative height distribution of stationary periodic Gaussian signals (one dimensional interfaces) displaying a 1/f^alpha power spectrum. For 0<alpha<1 (regime of decaying correlations), we observe that the mathematically established limiting distribution (Fisher-Tippett-Gumbel distribution) is ap

Momme Winkelnkemper, Andrei Schliwa, Dieter Bimberg

We present an eight-band k.p model for the calculation of the electronic structure of wurtzite semiconductor quantum dots (QDs) and its application to indium gallium nitride (InGaN) QDs formed by composition fluctuations in InGaN layers. The eight-band k.p model accounts for strain effects, piezoelectric and pyroelectricity, spin-orbit and crystal field spli

Daijiro Yoshioka

Bound states around an impurity are investigated for a two dimensional electron system in a strong magnetic field. Long-range Coulomb potential and related potentials are considered. Schrödinger equation is solved numerically to obtain the bound states. The energy and wave function of these bound states are indirectly observed by the scanning tunneling spect

R. Seguin, S. Rodt, A. Schliwa, K. Pötschke

A comprehensive study of the exchange interaction between charge carriers in self-organized InAs/GaAs quantum dots is presented. Single quantum-dot cathodoluminescence spectra of quantum dots of different sizes are analyzed. Special attention is paid to the energetic structure of the charged excited exciton (hot trion). A varying degree of intermixing within

J. Deisenhofer, R. M. Eremina, A. Pimenov, T. Gavrilova

We investigated the magnetic properties of the system CuTe2O5 by susceptibility and electron spin resonance measurements. The anisotropy of the effective g-factors and the ESR linewidth indicates that the anticipated structural dimer does not correspond to the singlet-forming magnetic dimer. Moreover, the spin susceptibility of CuTe2O5 can only be described

M. W. Haverkort, Z. Hu, J. C. Cezar, T. Burnus

Using soft x-ray absorption spectroscopy and magnetic circular dichroism at the Co-$L_{2,3}$ edge we reveal that the spin state transition in LaCoO$_{3}$ can be well described by a low-spin ground state and a triply-degenerate high-spin first excited state. From the temperature dependence of the spectral lineshapes we find that LaCoO$_{3}$ at finite temperat

T. Domanski, A. Donabidowicz

By means of the continuous unitary transformation similar to a general scheme of the Renormalization Group (RG) procedure we study the issue of symmetry breaking and pairing instability in the system of interacting fermions. Constructing a generalized version of the Bogoliubov transformation we show that formation of the fermion pairs and their superconducti

I. Maruyama, N. Shibata, K. Ueda

The Fano-Kondo effect in zero-bias conductance is studied based on a theoretical model for the T-shaped quantum dot by the finite temperature density matrix renormalization group method. The modification of the two Fano line shapes at much higher temperatures than the Kondo temperature is also investigated by the effective Fano parameter estimated as a fitti

E. Akkermans, O. Assaf

We show that a new interference effect appears in the intensity fluctuations of photons multiply scattered by an atomic gas of large optical depth b. This interference occurs only for scattering atoms that are Zeeman degenerate and it leads to a deviation from the Rayleigh law. The fluctuations measured by their variance, display a resonance peak as a functi

J. J. Xiao, K. Yakubo, K. W. Yu

Coupled plasmon modes are studied in graded plasmonic waveguides, which are periodic chains of metallic nanoparticles embedded in a host with gradually varying refractive indices. We identify three types of localized modes called &#34;light&#34;, &#34;heavy&#34;, and &#34;light-heavy&#34; plasmonic gradons outside the passband, according to various degrees o

Isao Maruyama, Tetsuji Koide, Yasuhiro Hatsugai

A new type of external fields violating the particle number preservation is studied in one-dimensional strongly correlated systems by the Density Matrix Renormalization Group method. Due to the U(1) symmetry breaking, the ground state has fluctuation of the total particle number, which implies injection of electrons and holes from out of the chain. This char

Indu Dhiman, A. Das, S. K. Dhar, P. Raychaudhuri

We report neutron diffraction measurements on CeNi4Mn, which has recently been identified as a soft ferromagnet (Tc ~ 140 K) with a sizeable spin-transport polarization. Our data show conclusively that the Mn atoms occupy a unique site (4c) in the unit cell, which has the symmetry of the cubic MgCu4Sn-type structure. We infer a moment of 4.6 mu_B on Mn at 17

R. N. Bhowmik, R. Ranganathan

Magnetic relaxation in antiferromagnetic CoRh$_2$O$_4$ nanoparticles is investigated at 2 K by cooling the sample from a temperature (70 K) well above the antiferromagnetic ordering temperature at 27 K, following zero field cooled (ZFC) and field cooled (FC) process. In ZFC process, the sample at 2 K is subsequently followed by magnetic field on and off sequ

Jong Soo Lim, Mahn-Soo Choi, M. Y. Choi

We study quantum dissipative dynamics of entanglement in the spin-boson model, described by the generalized master equation. We consider the two opposite limits of pure-dephasing and relaxation models, measuring the degree of entanglement with the concurrence. When the Markovian approximation is employed, entanglement is shown to decay exponentially in both

Abdel-Khalek Farid, Eugene Mishchenko

The interplay of electron-electron interactions and spin-orbit coupling leads to a new contribution to the homogeneous optical conductivity of the electron liquid. The latter is known to be insensitive to many-body effects for a conventional electron system with parabolic dispersion. The parabolic spectrum has its origin in the Galilean invariance which is b

P. G. Silvestrov, E. G. Mishchenko

Semiclassical solutions of two-dimensional Schrodinger equation with spin-orbit interaction and smooth potential are considered. In the leading order, spin polarization is in-plane and follows the evolution of the electron momentum for a given subband. Out-of-plane spin polarization appears as a quantum correction, for which an explicit expression is obtaine

Takahiko Matsubara

Fourier methods are fundamental tools to analyze random fields. Statistical structures of homogeneous Gaussian random fields are completely characterized by the power spectrum. In non-Gaussian random fields, polyspectra, higher-order counterparts of the power spectrum, are usually considered to characterize statistical information contained in the fields. Ho

Victor P. Debattista, Juntai Shen

A large fraction of barred galaxies host secondary bars that are embedded in their large-scale primary counterparts. These are common also in gas poor early-type barred galaxies. The evolution of such double-barred galaxies is still not well understood, partly because of a lack of realistic $N$-body models with which to study them. Here we report a new mecha

Cecilia Lunardini

I review the status and perspectives of the research on the diffuse flux of (core collapse) supernova neutrinos (DF). In absence of a positive signal, several upper bounds exist in different detection channels. Of these, the strongest is the limit from SuperKamiokande (SK) of 1.2 electron antineutrinos cm^-2 s^-1 at 90% confidence level above 19.3 MeV of neu

G. Tenorio-Tagle, C. Munoz-Tunon, E. Perez, S. Silich

We review the structural properties of giant extragalactic HII regions and HII galaxies based on two dimensional hydrodynamic calculations, and propose an evolutionary sequence that accounts for their observed detailed structure. The model assumes a massive and young stellar cluster surrounded by a large collection of clouds. These are thus exposed to the mo

Sergey V. Marchenko, Anthony F. J. Moffat

The massive, luminous Population I Wolf-Rayet stars can be considered as stars with the highest known sustained mass loss rates. Around 10% of WR stars may form carbon-rich dust in their dense and inhomogeneous winds. Though we are yet to find how dust is formed in such an extremely hostile environment, we have made substantial progress over the past decade.

Nathan Smith, Gary J. Ferland

We present models that reproduce the observed double-shell structure of the Homunculus Nebula around eta Carinae, including the stratification of infrared H2 and [FeII] emission seen in data obtained with the Phoenix spectrograph on Gemini South, as well as the corresponding stratified grain temperature seen in thermal-infrared data. Tuning the model to matc

Thomas F. Droege, Michael W. Richmond, Michael P. Sallman, Robert P. Creager

The Amateur Sky Survey (TASS) is a loose confederation of amateur and professional astronomers. We describe the design and construction of our Mark IV systems, a set of wide-field telescopes with CCD cameras which take simultaneous images in the $V$ and $I_C$ passbands. We explain our observational procedures and the pipeline which processes and reduces the

Thomas A. Sebring, Riccardo Giovanelli, Simon Radford, Jonas Zmuidzinas

Cornell, California Institute of Technology (Caltech), and Jet Propulsion Lab (JPL) have joined together to study development of a 25 meter sub-millimeter telescope (CCAT) on a high peak in the Atacama region of northern Chile, where the atmosphere is so dry as to permit observation at wavelengths as short as 200 micron. The telescope is designed to deliver

Magaretha L. Pretorius, Christian Knigge

Aims: We present discovery observations of the new cataclysmic variable star (CV) 1RXS J092737.4-191529, as well as spectra and photometry of SY Vol. The selection technique that turned up these two CVs is described; it should be efficient for finding dwarf novae with high outburst duty cycles. Methods: Two very common observational features of CVs, namely o

Mark R. Krumholz

One of the outstanding puzzles about star formation is why it proceeds so slowly. Giant molecular clouds convert only a few percent of their gas into stars per free-fall time, and recent observations show that this low star formation rate is essentially constant over a range of scales from individual cluster-forming molecular clumps in the Milky Way to entir

Ezequiel Treister, C. Megan Urry

In order to study the evolution of the relative fraction of obscured Active Galactic Nuclei (AGN) we constructed the largest sample to date of AGN selected in hard X-rays. The full sample contains 2341 X-ray-selected AGN, roughly 4 times the largest previous samples studied in this connection. Of these, 1229 (53%) have optical counterparts for which redshift

Andreas A. Berlind, Eyal Kazin, Michael R. Blanton, Sebastian Pueblas

We investigate the clustering of galaxy groups and clusters in the SDSS using the Berlind et al. (2006) group sample, which is designed to identify galaxy systems that each occupy a single dark matter halo. We estimate group masses from their abundances, and measure their relative large-scale bias as a function of mass. Our measurements are in agreement with

M. E. Gonzalez, V. M. Kaspi, M. J. Pivovaroff, B. M. Gaensler

We present results from Chandra and XMM-Newton observations of the radio pulsar B1046-58. A high-resolution spatial analysis reveals an asymmetric pulsar wind nebula (PWN) ~6&#34;x11&#34; in size. The combined emission from the pulsar and its PWN is faint, with a best-fit power-law photon index of $Γ$=1.7 and unabsorbed luminosity of ~10^32 ergs/s in the 0.5

M. E. Gonzalez, V. M. Kaspi, F. Camilo, B. M. Gaensler

The existence of radio pulsars having inferred magnetic fields in the magnetar regime suggests that possible transition objects could be found in the radio pulsar population. The discovery of such an object would contribute greatly to our understanding of neutron star physics. Here we report on unusual X-ray emission detected from the radio pulsar PSR J1119-

S. Colafrancesco

Multi-frequency (X-ray, optical and radio) observations of galaxy clusters indicate that the atmospheres of these cosmic structures consist of a complex structure of thermal (hot and warm) and non-thermal (with different origin and spectra) distribution of electrons (and protons) which is, therefore, far from its modelling as a single, thermal electronic gas

P. R. McCullough

Specularly reflected light, or glint, from an ocean surface may provide a useful observational tool for studying extrasolar terrestrial planets. Detection of sea-surface glints would differentiate ocean-bearing terrestrial planets, i.e. those similar to Earth, from other terrestrial extrasolar planets. The brightness and degree of polarization of both sea-su

A. Marcolini, A. D&#39;Ercole, F. Brighenti, S. Recchi

We present 3D hydrodynamic simulations aimed at studying the dynamical and chemical evolution of the interstellar medium in dwarf spheroidal galaxies. This evolution is driven by the explosions of Type II and Type Ia supernovae, whose different contribution is explicitly taken into account in our models. We compare our results with avaiable properties of the

S. Mieske, M. Hilker, L. Infante, C. Mendes de Oliveira

AIMS: We analyse the photometric properties of the early-type Fornax cluster dwarf galaxy population, based on a wide field imaging study of the central cluster area in V and I. We used the instrument/telescope combination IMACS/Magellan at Las Campanas Observatory, providing much larger light collecting area and better image resolution than previous surveys

Rene Oudmaijer

Circumstellar disks play an important role in many stages of the evolution of stars. However, it is only possible to directly image circumstellar disks for a few of the nearest stars. For massive stars, the situation is even more difficult, as they are on average further away than the more numerous low mass stars. Here, we discuss spectropolarimetry which is

N. A. Tikhonov

Stellar photometry obtained using the Hubble Space Telescope is used to study the distributions of the number densities of stars of various ages in 12 irregular and dwarf spiral galaxies viewed edge-on. Two subsystems can be distinguished in all the galaxies: a thin disk comprised of young stars and a thick disk containing a large fraction of the old stars (

D. Guetta, V. D&#39;Elia, F. Fiore, M. L. Conciatore

We present a detailed study of the spectral and temporal properties of the X-ray flares emission of several GRBs. We select a sample of GRBs which X-ray light curve exhibits large amplitude variations with several rebrightenings superposed on the underlying three-segment broken powerlaw that is often seen in Swift GRBs. We try to understand the origin of the

Alan B. Whiting

In 1925 Sir James Jeans calculated that a star made up of an ideal gas, generating energy as a moderately positive function of temperature and density, could not exist. Such stars would be unstable to oscillations of increasing size. It appears that the flaw in his calculation has never been clearly explained, especially the physical basis for it. I conclude

N. A. Tikhonov

Stellar photometry of nearby irregular galaxies of the Local Group is used to identify and study the young and old stellar populations of these galaxies. An analysis of the spatial distributions of stars of different ages in face-on galaxies shows that the young stellar populations in irregular galaxies are concentrated toward the center, and form local inho

R. Bonito, S. Orlando, G. Peres, F. Favata

Recently X-ray emission from protostellar jets has been detected with both XMM-Newton and Chandra satellites, but the physical mechanism which can give rise to this emission is still unclear. We performed an extensive exploration of a wide space of the main parameters influencing the jet/ambient interaction. Aims include: 1) to constrain the jet/ambient inte

Claude Bertout, Francoise Genova

Aims: This is the first paper in a series dedicated to investigating the kinematic properties of nearby associations of young stellar objects. Here we study the Taurus-Auriga association, with the primary objective of deriving kinematic parallaxes for individual members of this low-mass star-forming region. Methods: We took advantage of a recently published

Dariusz Gora, Markus Roth, Alessio Tamburro

We present a study about the possibility to detect neutrino induced extensive air showers at the Pierre Auger Observatory. The Monte Carlo simulations performed take into account the details of the neutrino propagation inside the Earth, the air as well as the surrounding mountains which are modelled by a digital elevation map. Details on the sensitivity with

Sylvie Vauclair

Studying the internal structure of exoplanets-host stars compared to that of similar stars without detected planets is particularly important for the understanding of planetary formation. The observed overmetallicity of stars around which planets have been detected may be a hint in that respect. In this framework, asteroseismic studies represent an excellent

Sylvie Vauclair, Matthieu Castro, Stephane Charpinet, Marion Laymand

Studying the internal structure of exoplanets-host stars compared to that of similar stars without detected planets is particularly important for the understanding of planetary formation. The observed overmetallicity of stars with planets may be a hint in that respect. Although it is obviously related to the physical processes which occur during the early ph

M. Laymand, S. Vauclair

{This paper presents detailed analysis and modelisation of the star HD17051 (alias $ι$ Hor), which appears as a specially interesting case among exoplanet host stars. As most of these stars, $ι$ Hor presents a metallicity excess which has been measured by various observers who give different results, ranging from [Fe/H] = 0.11 to 0.26, associated with differ

Stefan Uttenthaler, Josef Hron, Thomas Lebzelter, Maurizio Busso

We searched for Technetium (Tc) in a sample of bright oxygen-rich asymptotic giant branch (AGB) stars located in the outer galactic bulge. Tc is an unstable element synthesised via the s-process in deep layers of AGB stars, thus it is a reliable indicator of both recent s-process activity and third dredge-up. We aim to test theoretical predictions on the lum

C. Catala, E. Alecian, J. -F. Donati, G. A. Wade

The general context of this paper is the study of magnetic fields in the pre-main sequence intermediate mass Herbig Ae/Be stars. Magnetic fields are likely to play an important role in pre-main sequence evolution at these masses, in particular in controlling the gains and losses of stellar angular momentum. The particular aim of this paper is to announce the

Gabriel Torok, Marek A. Abramowicz, Zdenek Stuchlik, Eva Sramkova

In the Galactic microquasars with double peak kHz quasi-periodic oscillations (QPOs), the ratio of the two frequencies is 3:2. This supports the suggestion that double peak kHz QPOs are due to a non-linear resonance between two modes of accretion disk oscillations. For the microquasars with known mass, we briefly compare the black hole spin estimates based o

Aya Kubota, Tadayasu Dotani, Jean Cottam, Taro Kotani

We present the results of six Suzaku observations of the recurrent black hole transient 4U1630-472 during its decline from outburst from February 8 to March 23 in 2006. All observations show the typical high/soft state spectral shape in the 2-50keV band, roughly described by an optically thick disk spectrum in the soft energy band plus a weak power-law tail

Naoko Tsunoda, Aya Kubota, Masaaki Namiki, Masahiko Sugiho

We report on the results of detailed spectral studies of the ultra-luminous X-ray source (ULX), M81 X-9 (Holmberg IX X-1), made with XMM-Newton on 2001 April 22 and with ASCA on 1999 April 6. On both occasions, the source showed an unabsorbed 0.5-10 keV luminosity of ~2E40 erg/s (assuming a distance of 3.4Mpc) and a soft spectrum apparently represented by a

Y. Shi, G. H. Rieke, D. C. Hines, K. D. Gordon

We discuss images of M87 from 3.6 to 160 um obtained with Spitzer. As found previously, there is an excess in the far infrared over a simple power law interpolation from the radio to the resolved nonthermal features in the mid-infrared and optical. We show that this excess is most likely warm dust in the galaxy itself, and that the properties of this emissio

Lindsay King, Virginia Corless

The distribution of mass on galaxy cluster scales is an important test of structure formation scenarios, providing constraints on the nature of dark matter itself. Several techniques have been used to probe the mass distributions of clusters, sometimes yielding results which are discrepant, or at odds with clusters formed in simulations - for example giving

M. V. van der Sluys, F. Verbunt, O. R. Pols

We investigate the formation of the ten double-lined double white dwarfs that have been observed so far. A detailed stellar evolution code is used to calculate grids of single-star and binary models and we use these to reconstruct possible evolutionary scenarios. We apply various criteria to select the acceptable solutions from these scenarios. We confirm th

J. Harrington, B. Hansen, S. Luszcz, S. Seager

The star upsilon Andromeda is orbited by three known planets, the innermost of which has an orbital period of 4.617 days and a mass at least 0.69 that of Jupiter. This planet is close enough to its host star that the radiation it absorbs overwhelms its internal heat losses. Here we present the 24 micron light curve of this system, obtained with the Spitzer S

Erica Flapan, Blake Mellor, Ramin Naimi

We show that, given any $n$ and $α$, every embedding of any sufficiently large complete graph in $\mathbb{R}^3$ contains an oriented link with components $Q_1$, ..., $Q_n$ such that for every $i\not =j$, $|\lk(Q_i,Q_j)|\geqα$ and $|a_2(Q_i)|\geqα$, where $a_{2}(Q_i)$ denotes the second coefficient of the Conway polynomial of $Q_i$.

Amer Shreim, Peter Grassberger, Walter Nadler, Björn Samuelsson

We study networks representing the dynamics of elementary 1-d cellular automata (CA) on finite lattices. We analyze scaling behaviors of both local and global network properties as a function of system size. The scaling of the largest node in-degree is obtained analytically for a variety of CA including rules 22, 54 and 110. We further define the \emph{path

Hsiao-Kuan Yuan, Uday K. Chettiar, Wenshan Cai, Alexander V. Kildishev

Experimental demonstration of a negative permeability due to near-field coupling of periodic thin silver strips is presented. Two samples with different strip thicknesses are fabricated; optical measurements of the samples confirm our initial design projections by showing the real part of permeability to be about -1 for the sample with thinner strips and -0.

Jacob G. Foster, David V. Foster, Peter Grassberger, Maya Paczuski

The simplest null models for networks, used to distinguish significant features of a particular network from {\it a priori} expected features, are random ensembles with the degree sequence fixed by the specific network of interest. These &#34;fixed degree sequence&#34; (FDS) ensembles are, however, famously resistant to analytic attack. In this paper we intr

J. L. Chkareuli, C. D. Froggatt, H. B. Nielsen

We consider a class of field theories with a four-vector field $A_μ(x)$ in addition to other fields supplied with a global charge symmetry - theories which have partial gauge symmetry in the sense of only imposing it on those terms in the Lagrangian density which have derivatives as factors in them. We suppose that spontaneous Lorentz invariance breaking occ

Seiji Yunoki

Low-lying one-particle anomalous excitations are studied for Gutzwiller projected strongly correlated BCS states. It is found that the one-particle anomalous excitations are highly coherent, and the numerically calculated spectrum can be reproduced quantitatively by a renormalized BCS theory, thus strongly indicating that the nature of low-lying excitations

W. A. Coish, Daniel Loss

We show theoretically that arbitrary coherent rotations can be performed quickly (with a gating time ~1 ns) and with high fidelity on the spin of a single confined electron using control of exchange only, without the need for spin-orbit coupling or ac fields. We expect that implementations of this scheme would achieve gate error rates on the order of η~ 10^{

André van Tonder, Miquel Dorca

We investigate the non-perturbative quantization of phantom and ghost degrees of freedom by relating their representations in definite and indefinite inner product spaces. For a large class of potentials, we argue that the same physical information can be extracted from either representation. We provide a definition of the path integral for these theories, e

James B. Hartle

Human languages employ constructions that tacitly assume specific properties of the limited range of phenomena they evolved to describe. These assumed properties are true features of that limited context, but may not be general or precise properties of all the physical situations allowed by fundamental physics. In brief, human languages contain `excess bagga

Danilo Marchesini, Pieter van Dokkum, Ryan Quadri, Gregory Rudnick

We present the rest-frame optical (B, V, and R band) luminosity functions (LFs) of galaxies at 2<z<3.5, measured from a K-selected sample constructed from the deep NIR MUSYC, the ultradeep FIRES, and the GOODS-CDFS. This sample is unique for its combination of area and range of luminosities. The faint-end slopes of the LFs at z>2 are consistent with those at

Maximilien Gadouleau, Zhiyuan Yan

In this paper, we study properties of rank metric codes in general and maximum rank distance (MRD) codes in particular. For codes with the rank metric, we first establish Gilbert and sphere-packing bounds, and then obtain the asymptotic forms of these two bounds and the Singleton bound. Based on the asymptotic bounds, we observe that asymptotically Gilbert-V

Alejandro Corichi, Tatjana Vukasinac, Jose A. Zapata

In this paper, a version of polymer quantum mechanics, which is inspired by loop quantum gravity, is considered and shown to be equivalent, in a precise sense, to the standard, experimentally tested, Schroedinger quantum mechanics. The kinematical cornerstone of our framework is the so called polymer representation of the Heisenberg-Weyl (H-W) algebra, which

Z. -H. Pan, P. Richard, A. V. Fedorov, T. Kondo

We use angle-resolved photoemission to unravel the quasiparticle decoherence process in the high-$T_c$ cuprates. The coherent band is highly renormalized, and the incoherent part manifests itself as a nearly vertical ``dive&#39;&#39; in the $E$-$k$ intensity plot that approaches the bare band bottom. We find that the coherence-incoherence crossover energies

Alexander Gorodnik, Hee Oh, Nimish Shah

Let V be an affine symmetric variety defined over Q. We compute the asymptotic distribution of the angular components of the integral points in V. This distribution is described by a family of invariant measures concentrated on the Satake boundary of V. In the course of the proof, we describe the structure of the Satake compactifications for general affine s

Hasan Yuksel, Matthew D. Kistler

Gamma-ray bursts, which are among the most violent events in the universe, are one of the few viable candidates to produce ultrahigh energy cosmic rays. Recently, observations have revealed that GRBs generally originate from metal-poor galaxies and do not directly trace cosmic star formation, as might have been assumed from their association with core-collap

Pierre Sikivie

Outline: 1. Thermal axions 2. Axion field evolution 3. The domain wall problem 4. Cold axions 5. Axion miniclusters 6. Axion isocurvature perturbations

Mark M. Wilde, Federico Spedalieri, Jonathan P. Dowling, Hwang Lee

We design a controlled-phase gate for linear optical quantum computing by using photodetectors that cannot resolve photon number. An intrinsic error-correction circuit corrects errors introduced by the detectors. Our controlled-phase gate has a 1/4 success probability. Recent development in cluster-state quantum computing has shown that a two-qubit gate with

Philipp Werner, Andrew J. Millis

A powerful new impurity solver is shown to permit a systematic study of the doping driven Mott transition in a one-band Hubbard model within the framework of single-site dynamical mean field theory. At small dopings and large interaction strengths we are able access low enough temperatures that a reliable extrapolation to temperature T=0 may be performed, an

J. Hansen, M. Sato, R. Ruedy, P. Kharecha

We carry out climate simulations for 1880-2003 with GISS modelE driven by ten measured or estimated climate forcings. An ensemble of climate model runs is carried out for each forcing acting individually and for all forcing mechanisms acting together. We compare side-by-side simulated climate change for each forcing, all forcings, observations, unforced vari

Adrian Ioana

For any $2\leq n\leq \infty$, we construct a concrete 1-parameter family of non-orbit equivalent actions of the free group $\Bbb F_n$. These actions arise as diagonal products between a generalized Bernoulli action and the action $\Bbb F_n\curvearrowright (\Bbb T^2,λ^2)$, where $\Bbb F_n$ is seen as a subgroup of SL$_2(\Bbb Z)$.

Ya. V. Fominov, A. F. Volkov, K. B. Efetov

We consider a SFS Josephson junction made of two superconductors S and a multidomain ferromagnet F with an in-plane magnetization. We assume that the neighboring domains of the ferromagnet are separated by Neel domain walls. An odd-frequency triplet long-range component of superconducting correlations arises in the domain walls and spreads into the domains o

Ethan T. Neil, Charles D. Bailyn, Bethany E. Cobb

We present the results of seven years of K-band monitoring of the low-mass X-ray binary GRS 1915+105. Positive correlations between the infrared flux and the X-ray flux and X-ray hardness are demonstrated. Analysis of the frequency spectrum shows that the orbital period of the system is $P_{orb}= 30.8 \pm 0.2$ days. The phase and amplitude of the orbital mod

H. Aratyn, J. F. Gomes, A. H. Zimerman

Different gauge copies of the Ablowitz-Kaup-Newell-Segur (AKNS) model labeled by an angle $\theta$ are constructed and then reduced to the two-component Camassa--Holm model. Only three different independent classes of reductions are encountered corresponding to the angle $\theta$ being 0, $\pi/2$ or taking any value in the interval $0<\theta<\pi/2$. This con

R. Hanson, L. P. Kouwenhoven, J. R. Petta, S. Tarucha

This review describes the physics of spins in quantum dots containing one or two electrons, from an experimentalist&#39;s viewpoint. Various methods for extracting spin properties from experiment are presented, restricted exclusively to electrical measurements. Furthermore, experimental techniques are discussed that allow for: (1) the rotation of an electron

Ed Bueler, Jed Brown

This three section report can be regarded as an extended appendix to (Bueler, Brown, and Lingle 2006). First we give the detailed construction of an exact solution to a standard continuum model of a cold, shallow, and thermocoupled ice sheet. The construction is by calculation of compensatory accumulation and heat source functions which make a chosen pair of

Elliott H. Lieb, Robert Seiringer, Jakob Yngvason

After recalling briefly the connection between spontaneous symmetry breaking and off-diagonal long range order for models of magnets a general proof of spontaneous breaking of gauge symmetry as a consequence of Bose-Einstein Condensation is presented. The proof is based on a rigorous validation of Bogoliubov&#39;s $c$-number substitution for the ${\bf k}={\b

J. B. Conrey, N. C. Snaith

We use the conjecture of Conrey, Farmer and Zirnbauer for averages of ratios of the Riemann zeta function to calculate all the lower order terms of the triple correlation function of the Riemann zeros. A previous approach was suggested in 1996 by Bogomolny and Keating taking inspiration from semi-classical methods. At that point they did not write out the an

G. Orso

We investigate two-component attractive Fermi gases with imbalanced spin populations in trapped one dimensional configurations. The ground state properties are determined within local density approximation, starting from the exact Bethe-ansatz equations for the homogeneous case. We predict that the atoms are distributed according to a two-shell structure: a

Thomas S. Deisboeck, Zhihui Wang

Assuming that there is feedback between an expanding cancer system and its organ-typical microenvironment, we argue here that such local tumor growth is guided by co-existence rather than competition with the surrounding tissue. We then present a novel concept that understands cancer dissemination as a biological mechanism to evade the specific carrying capa

Pere Talavera

We compute the drag force exerted on a quark and a di-quark systems in a background dual to large-N QCD at finite temperature. We find that appears a drag force in the former setup with flow of energy proportional to the mass of the quark while in the latter there is no dragging as in other studies. We also review the screening length.

Thomas Heimburg, Andrew D. Jackson

The Hodgkin-Huxley model of nerve pulse propagation relies on ion currents through specific resistors called ion channels. We discuss a number of classical thermodynamic findings on nerves that are not contained in this classical theory. Particularly striking is the finding of reversible heat changes, thickness and phase changes of the membrane during the ac

Ariel Edery

We study the Casimir piston for massless scalar fields obeying Dirichlet boundary conditions in a three dimensional cavity with sides of arbitrary lengths $a,b$ and $c$ where $a$ is the plate separation. We obtain an exact expression for the Casimir force on the piston valid for any values of the three lengths. As in the electromagnetic case with perfect con

Akira Yasuhara

For an $n$-component link $L$, the Milnor&#39;s isotopy invariant is defined for each multi-index $I=i_1i_2...i_m (i_j\in\n)$. Here $m$ is called the length. Let $r(I)$ denote the maximam number of times that any index appears. It is known that Milnor invariants with $r=1$ are link-homotopy invariant. N. Habegger and X. S. Lin showed that two string links ar

A. Yu. Smirnov

Physics interpretation of the ``magic&#39;&#39; baseline, $L_{magic}$, that can play important role in future oscillation experiments is given. The ``magic&#39;&#39; baseline coincides with the refraction length, $l_0$. The latter, in turn, approximately equals the oscillation length in matter at high energies. Therefore at the baseline $L = l_0$ the oscilla

Junpeng Cao, Yuzhu Jiang, Yupeng Wang

An exactly solvable model describing the low density limit of the spin-1 bosons in a one-dimensional optical lattice is proposed. The exact Bethe ansatz solution shows that the low energy physics of this system is described by a quantum liquid of spin singlet bound pairs. Motivated by the exact results, a mean-field approach to the corresponding three-dimens

R. S. Priddey, S. C. Gallagher, K. G. Isaak, R. G. Sharp

Using the SCUBA bolometer array on the JCMT, we have carried out a submillimetre survey of Broad Absorption Line quasars (BALQs). The sample has been chosen to match, in redshift and optical luminosity, an existing benchmark 850um sample of radio-quiet quasars, allowing a direct comparison of the submm properties of BAL quasars relative to the parent radio-q

S. Lacour, E. Thiébaut, G. Perrin

The correction of the influence of phase corrugation in the pupil plane is a fundamental issue in achieving high dynamic range imaging. In this paper, we investigate an instrumental setup which consists in applying interferometric techniques on a single telescope, by filtering and dividing the pupil with an array of single-mode fibers. We developed a new alg

Michael M. Schein

Let F be a totally real field and p an odd prime. If r is a continuous, semisimple, totally odd mod p representation of the absolute Galois group of F which is tamely ramified at all places of F dividing p, then we formulate a conjecture specifying the weights for which r is modular. This extends the conjecture of Diamond, Buzzard, and Jarvis, which supposed

Steven Blusk

We present several results on hadronic D meson decays. We report on results from the scan of the energy region from 3970 MeV to 4260 MeV, which was used to determine an optimal energy to carry out the D_s physics program of CLEO-c. Improved measurements of inclusive and exclusive D and D_s branching fractions are presented. We also show results on Dalitz ana

Steven Blusk

We present measurements of the branching fractions of the decays, D-->K^0_{S,L}pi. The measured asymmetry shows that B(D^0--> K^0_S pi^0) is not equal to B(D^0--> K^0_L pi^0), as expected. We also find that B(D^+ --> K^0_S pi^+) is statistically compatible with B(D^+ --> K^0_L pi^+). Lastly, we present a recent measurement of the branching fraction of the do

Huanyang Chen, Xudong Luo, Hongru Ma

Based on the formalism developed by Psarobas et al [Phys. Rev. B 62, 278(2000)], which using the multiple scattering theory to calculate properties of simple phononic crystals, we propose a very simple method to study the NaCl-type phononic crystal. The NaCl-type phononic crystal consists of two kinds of non-overlapping elastic spheres with different mass de

Rui M. G. Reis, Richard J. Szabo, Alessandro Valentino

We study the classification of D-branes and Ramond-Ramond fields in Type I string theory by developing a geometric description of KO-homology. We define an analytic version of KO-homology using KK-theory of real C*-algebras, and construct explicitly the isomorphism between geometric and analytic KO-homology. The construction involves recasting the Cl(n)-inde

Abdelkader Mokkadem, Mariane Pelletier

A stochastic algorithm for the recursive approximation of the location $θ$ of a maximum of a regression function was introduced by Kiefer and Wolfowitz [Ann. Math. Statist. 23 (1952) 462--466] in the univariate framework, and by Blum [Ann. Math. Statist. 25 (1954) 737--744] in the multivariate case. The aim of this paper is to provide a companion algorithm t

J. Hansen, M. Sato, R. Ruedy, P. Kharecha

We investigate the issue of "dangerous human-made interference with climate" using simulations with GISS modelE driven by measured or estimated forcings for 1880-2003 and extended to 2100 for IPCC greenhouse gas scenarios as well as the 'alternative' scenario of Hansen and Sato. Identification of 'dangerous' effects is partly subjective, but we find evidence

pp2pp Collaboration, S. Bultmann, I. H. Chiang, R. E. Chrien

We present the first measurements of the double spin asymmetries A_NN and A_SS at sqrt{s}=200 GeV, obtained by the pp2pp experiment using polarized proton beams at the Relativistic Heavy Ion Collider (RHIC). The data were collected in the four momentum transfer t range 0.01<|t|<0.03 (GeV/c)^2. The measured asymmetries, which are consistent with zero, allow u

R. A. Konoplya

We analyze motion of massless and massive particles around black holes immersed in an asymptotically uniform magnetic field and surrounded by some mechanical structure, which provides the magnetic field. The space-time is described by Preston-Poisson metric, which is the generalization of the well-known Ernst metric with a new parameter, tidal force, charact